sweetheart
by closingdoors
Summary: Under Fire AU, set in season four. This time, it's Ryan and Castle stuck in the building. She wants her love to be the last thing he hears. COMPLETE.


if you must die, sweetheart,  
die knowing your life was my life's best part  
**\- you, keaton henson**

* * *

**Disclaimer: **Still not mine. Also, yeah, I know, this episode aired forever ago - I imagine this version take place after Killshot; before Ryan's wedding.

* * *

The bile is raw and thick in her throat.

Lanie's arm around her waist is the only thing preventing her from crumpling, from her knees hitting the floor. She is weak, she is nothing; she can't save him, can't save Castle - what is the _point _of her? What is the point of her standing here and watching the flames engulf the building knowing that there is nothing she can do? She is nothing. She is nothing. She is nothing.

She is nothing.

Jenny hiccups, leaning on Esposito for support as she speaks to Ryan over the phone.

There's nothing. Nothing they can do.

She is nothing.

Kate closes her eyes, exhales softly and forgets the miracle of existing. She is _not here_. Castle not inside that building. They're standing over someone else's corpse, any place other than here, he's making ill-timed jokes and looking at her with cool, water-hue eyes. He is not choking on smoke, blocking the passageways of his lungs; he is not surrounded from head to toe in ash, already smouldering; he is not surrounded by flames, he is not dying. He's _Castle. _He's her partner. He can't be dying.

He can't.

"Kate."

With one squeeze at her waist, Lanie grabs her attention. Her eyes open but everything is blurry, moving fragments around her. Jenny's words of _we were supposed to be getting married _and _I love __you, Kevin Ryan, _revolving around and around in her head on a constant loop. Nausea makes her stomach roll and then there's a solid weight in her hands, something plastic and heavy.

"It's Castle. He wants to speak to you," she thinks she hears. Jenny?

She is nothing.

"Kate."

Esposito this time, and her eyes manage to focus. His face is ashen, stricken, stripped away of bravery.

The bile rises again.

"There's not much time left," he says gently, guiding her hand with the phone sitting in it to her ear, "you should talk to him."

Kate nods, mouth opening but she's choking. Lanie rubs a hand down her spine.

"Kate?"

Castle.

Oxygen overwhelms her then and the weight of all of the things she had held back come pouring out of her. Fingers trembling, grappling with the phone and she's keening, shaking against Lanie. Words babble and swim in her head but there's nothing to say - what is there to say? It's too late, he's going to die, there is nothing that she can do. The fire department have given up; Jenny has said goodbye to her fiancé; she is supposed to say goodbye, too.

Oh God. Oh God. They're not supposed to have a goodbye. She was shot in the heart and survived - she was supposed to be healing, supposed to be stitching the haphazard pieces of herself back together, licking the salt from her wounds. How can she have been doing all of that, how could he have been waiting for her all of this time, how could all of this be destroyed by flames?

"Kate... It's okay," he promises, voice tinny through the phone, haggard, "It's - It'll be okay."

"No," is all that escapes, a sob, burning her throat. "Castle..."

Turning her eyes from the floor to the flames she feels them licking against her ribcage, burning down the foundations of her body. First goes the security of her bones, the back up weight of her muscles; her heart takes up all the space then, left alone to simmer and smoulder and sob while she buries her face into Lanie's shoulder. All the while she wishes it were him here. She would let him, she thinks. She would let him see her like this, let him comfort her - yes, she is broken and mottled with trauma and shaking from self-inflicted wounds. But he loves her. He loves her. She would let him.

Closing her eyes, she takes another deep breath.

"Would you... Will you look after Alexis, Kate?" He asks, and it almost sends her tumbling again. "She's - she's gonna need help applying to colleges and - and learning to live on her own, becoming a woman. Boyfriends. Career. You'll... Please..."

"No!" She protests, fire in her eyes, curling her hands into fists. "Don't you - Don't you _dare, _Castle - "

"Remember to check under her bed for monsters when she moves out. And her favourite hiding spot during laser tag is tucked under the stairs, but don't let her know that you know, because I've only just figured that one out. She gets an allowance, and I - I have it all sorted out in my will for when she's going to college and she needs her tuition paid and - "

"_Please," _Kate keens, slashing her hands across her eyes and seeing darkness, "Castle, you can't - "

"There's not much time left," he interrupts, and she feels the strength fade from his voice, "Kate. Please, please promise me."

"I will," she promises, "Oh God, Rick."

"It's okay. I'm - I tried to find a way. To get Ryan out," he tells her quickly, and she squeezes her eyes shut tight and pushes the tears back because _of course, _of course he tried to save Ryan instead of himself, "I can't... I don't know what to do, Kate. There's nothing I can do. Nothing anyone can do. Please don't blame yourself."

He knows her. Every last intricate, puzzle piece of her. Those cobwebs lurking in the back of her mind that he's dusted away, revealed as something extraordinary. Those black thick tangled roots of grief he's loosened, created a sense of security rather than a noose. Nobody else but him could ever do that; nobody else could know her in that way.

She is nothing.

"You don't just die."

He takes a deep breath.

"Kate..."

"I love you," she gasps out, hand raising as if to keep that secret trapped, to keep it alive. "You don't just _die."_

"You know I love you," he replies, solemn and accepting, only seconds left judging by the waver in his voice.

She wants her love to be the last thing he hears.

"I'm so sorry, Castle."

She is nothing.

"I love you, Rick, I - "

"Kate - "

The line crackles, and she gasps his name, calls for him but he doesn't answer. It goes dead and she's left staring at muted numbers on a screen. Gone.

He's gone.

Without thought, she drops the phone, staring numbly around her. There are flashes of visions. Jenny wrapped up in Esposito's comforting hug; Lanie's tearful eyes; the blank nothingness of the sky above her.

She is nothing.

Lanie pulls her into a hug. It's awkward, the height difference, their limbs tucked awkwardly against each other and her muscles straining as she accepts the comfort of her friends. Kate presses her lips together to keep the grief trapped inside, pushing against her ribs and pounding her heart. Her hands ball into fists against the back of Lanie's shirt and she shakes a little harder and feels her knees go weak. Some distant part of herself wishes to be out there looking for the killer, to be wielding a gun, to find the person that thought they could take Richard Castle away from her. Instead she sags against Lanie and says nothing more.

* * *

Ryan is lead out by the firefighters first.

Jenny cries out his name, running over to him and embracing him, ash and all. They're crying, telling each other they love each other and it burns.

She waits.

She does not meet Ryan's eye.

If Castle did not make it -

She doesn't want to know.

* * *

Castle doesn't make it without help.

He's older than Ryan, a little less fit. The fumes got to him quicker and he'd passed out first, no matter how long he'd tried to hang on for. When the firefighters first pull him from the building, it's on a stretcher, and she almost collapses. But then she sees the mask covering his face and then they're loading him into the back of an ambulance and won't accept _no_ as an answer when she asks to go with him.

Martha and Alexis are already there, of course, waiting at the hospital. The reception from Castle's daughter is ice cold, but that's okay - it could've been worse. It could've been so much worse.

He's awake soon after, and the doctor informs his family of his condition. Kate stands awkwardly on the fringes; neither in nor out.

But she sits on the chair outside his room when they first go in and waits her turn.

* * *

Martha emerges from the room twenty minutes later. Alexis blurs past her, not stopping to even look at her. The older woman, however, touches her shoulder gently.

"Katherine, dear, he's asking for you. Alexis and I are going to get coffee," she says, and Kate gets the hidden message. _We're still protecting him._

"Thank you, Martha."

The redhead leaves, sashaying down the hallway in a blur of colours. Kate takes a deep breath, pushing her palms into her sockets until she's seeing white, needing to prepare herself. Is there any way to prepare herself, though?

Or does she just let it happen?

Shaking her head, she stands on weak legs, fingers trembling as she wraps them around the door handle. The door itself squeaks slightly when she pulls it open and she grimaces, stepping inside to find his attention already drawn to her, saying nothing as she lets the door fall closed behind her. He's looking at her differently, though, in some ways off-putting; dissecting her like she's words on a page to interpret, to rearrange, to drain for meaning. But for the most part, it's whole. The way he looks at her. Like he's found something worth seeing and it makes her feel warmth, spreading from her chest and up and curling around her shoulders, forces her cheeks to flush. It's different to the burn of pain she had felt streak through her not even an hour before.

"Hey," he says, voice hoarse.

She smiles. "Hey."

Castle's weak, for the most part, but he lifts his hand, simply the crook of a few fingers. Her legs move towards him anyway, though, watching him carefully for any signs of distress. He doesn't show any when she stops at the side of his bed and curls her fingers around his.

The touch startles her, somehow, and she covers her mouth with her free hand, closing her eyes, gripping him harder. He's alive. He made it. They're here.

"It's okay now," he says - always has the right words for her.

"I thought I lost you," she tells him, letting her hand drop and meeting his eyes.

"Never," he promises, and she believes him.

Shaking her head slightly, Kate sits at his hip, fingers dancing across the lines of his palm.

"Castle..."

"We don't have to talk about it," he assures her. "If you're not ready."

She frowns. "No, I - I _want _to be... ready."

Castle threads his fingers with hers; strong. Proof that he's alive and that they made it, that they're not quite gone yet. She takes a deep breath and studies the way his hand encases hers. His thick fingers contrasting against her thinner ones. They're soft, his hands; writers hands - never quite experiencing anything other than words. She falls in love with them. The way they contradict themselves.

"Okay," he says slowly. "Then what do you want, Kate?"

Looking at him, waiting there, for her, she feels a pinch in her chest. An uneasiness. He's always leaving the decisions to her - she could walk out on him right now and he would still wait for the day she'll come back.

She stays.

Leaning down carefully, avoiding the wires and IV's between them that are helping him recover, Kate brushes her lips against his.

It's soft, and passes quickly. Nothing like their first kiss, in a cold alley just under a year ago, but this time it's real.

When she pulls away, it's only to rest her forehead against his, to breathe him in.

"You," she tells him. "Just you."

* * *

**The End**


End file.
